Abstract. Vulnerability is a complex concept involving a variety of disciplines from both the physical and socio-economic sciences. Currently, two opposite trends exist: the physical approach in which vulnerability is analysed as a sum of potential impacts on elements at risk and the social approach in which vulnerability is mostly viewed as a combination of socio-economic variables determining people's ability to anticipate, cope with and recover from a catastrophic event. Finding a way to combine these two approaches is a key issue for a global vulnerability assessment. In this paper we propose to combine elements from these two approaches through the analysis of the potential consequences of a high-magnitude flood event (recurrence interval (RI) > 100 years) on human and material stakeholders. To perform our analysis, we choose to upgrade an existing index, the Potential Damage Index (PDI; Puissant et al., 2013), by including social criteria. The PDI was originally developed to assess the physical consequences of hazards on the elements at risk (people, building and lands). It is based on the calculation of three sub-indices representing different types of direct and indirect consequences: physical injury consequences (PIC), structural and functional consequences (SFC), indirect functional consequences (IC). Here, we propose to add a fourth sub-index representing the social consequences. This new sub-index, called social consequences (SC) is obtained by combining criteria derived from INSEE French census data and a risk-perception survey conducted in the field. By combining the four indices (PIC, SFC, IC and SC), we managed to create a new index called the Potential Consequences Index (PCI). The new PCI was tested on the Upper Guil catchment to assess the consequences of a high-magnitude flood event (RI > 100 years). Results of the PDI were compared with the PCI and show significant differences. The upgrade to the PDI method provided us with many inputs. The introduction of elements from social vulnerability added an extra dimension to the total consequence map. It allowed us to qualify the potential physical consequences (physical injury, structural and functional consequences) on elements at risk by considering the global resilience of local communities.

10Vulnerability is a complex concept involving a variety of disciplines from physical and socio-economic sciences. Currently, two opposite trends exist: the physical approach in which vulnerability is analysed as potential impacts on the exposed elements; and the social approach in which vulnerability is viewed as a combination of socio-economic variables determining people's ability to anticipate before a catastrophic event, to react during it, and to recover after it. Finding a way to combine these two approaches is a key issue for a global vulnerability 15 assessment. The objective of this paper is to improve the Potential Damage Index (Puissant et al., 2013) originally developed to assess the physical, structural and functional consequences of landslide hazard, by including social and institutional criteria. These criteria, derived from INSEE French census data and risk perception survey were selected to represent the three main phases of risk management: preparedness, crisis management and recovery. The new Global Potential Damage Index is then applied on the Upper Guil Catchment to assess torrential floods. 20Results of the PDI are compared with the GPDI and show significant differences. GPDI scores are globally lower than PDI scores indicating that resilient population may qualify results obtained for physical consequences.